Gas Laws/Acids and Bases
C2H4O2+NaHCO3--->NaC2H3O2+H2O+CO2
Pressure.Gases are the only state of matter that can be compressed very tightly or expanded to fill a very large space. Pressure is force per unit area. The earth's gravity acts on air molecules to create a force, that of the air pushing on the earth. This is called atmospheric pressure. The units of pressure that are used are pascal (Pa), standard atmosphere (atm), and torr. 1 atm is the average pressure at sea level. It is usually used as a standard unit of pressure. The SI unit though, is the pascal. 101,325 pascals equals 1 atm. For laboratory work the atmosphere is very large. A more convenient unit is the torr. 760 torr equals 1 atm. A torr is the same unit as the mmHg (millimeter
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The Ideal gas law is the equation of state of a hypothetical ideal gas. It is a good approximation of the behavior of many gases under many conditions, although it has several limitations. It was first stated by Émile Clapeyron in 1834 as a combination of the empirical Boyle's law, Charles' law and Avogadro's Law.
An ideal gas can be characterized by three state variables: absolute pressure (P), volume (V), and absolute temperature (T). The relationship between them may be deduced from kinetic theory and is called the Ideal Gas Law.
The Ideal Gas Law: PV=nRT=NkT n = number of moles
R = universal gas constant = 8.3145 J/mol K
N = number of molecules k = Boltzmann constant = 1.38066 x 10-23 J/K = 8.617385 x 10-5 eV/K k = R/NA
NA = Avogadro's number = 6.0221 x 1023
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Standard Atmospheric pressure in these U.S. common units is 14.7 lb/in2, so this must be added to the gauge pressure above to get the absolute pressure.
Pressure Volume Temperature Relationships. Boyle's Law: The Pressure-Volume Law. “Boyle's law or the pressure-volume law states that the volume of a given amount of gas held at constant temperature varies inversely with the applied pressure when the temperature and mass are constant.”
Another way of describing it is saying that their products are constant.
When pressure goes up, volume goes down. When volume goes up, pressure goes down.
P1V1=P2V2=P3V3
This equation tells that the product off the initial volume and pressure is equal to the product off the volume and pressure after a change in one of them under constant temperature. “For example, if the initial volume was 500 mL at a pressure of 760 torr, when the volume is compressed to 450 mL, what is the pressure?
Plug in the values:
P1V1 = P2V2
(760 torr)(500 mL) = P2(450 mL)
760 torr x 500 mL/450 mL = P2 844 torr = P2
The pressure is 844 torr after